Patent GB-1388634-A (GB)
Title: Roll on capping head
IPC: B67B3/18
Filed: 1972-05-19
Abstract: 1388634 Capping bottles CONTINENTAL CAN CO Inc 19 May 1972 [9 July 1971] 23784/72 Heading B8T In a roll-on capping machine a valve operable by sensing means responsive to the presence of a cap blank on a container prevents the roll-on mechanisms from engaging the container neck if the blank is absent. The capping head assemblies 10 are mounted round a rotating turret frame 11. Each head is vertically lowered on to a container B with a cap blank C on its neck by a pneumatic piston 20 in a recess 21 in the frame 11 under the control of the cam track 17 and follower 15. The pistons 20 of the heads 10 are connected to a common air supply and the air from one passes to another as they are raised and lowered. As the frame 11 rotates, the heads are rotated by a pinion 46 on the stationary central shaft 12 and a pinion 45 on the outer sleeve 36 which is rotatably supported on the spindle 30 depending from each piston 20. As the piston 20 lowers the spindle 30 on to the cap C, the cap is engaged and shaped by a die at the end of the spindle assembly. A sensing shaft 160 is pushed upwardly against a spring 162 by the cap pushing upwardly a shaft 150 which extends through an axial bore 146 in the spindle 30. At the top of the shaft 150 is a valve 148 which, pushed upwardly from its seating 153 against a spring 152, admits compressed air through the bores 146, 154 into a recess 120 to depress a piston 121, lowering against a spring 123, a conical cam 122 which cams inwardly the rollers 66, 96 into engagement with the blank C. If the blank is absent from the container the shaft 160 drops below the die and the valve 148 remains closed so that the cam 122 is not lowered. The rolling mechanisms are carried in a member 60 at the lower end of the spindle 30. The thread forming mechanism consists of a cap engaging roller 66 supported on a shaft 68 which is rotatable in a bore 71 at the lower end of a supporting lever 65. The bore is sloped at right angles to the helix of the screwthread on the container. The shaft can move axially somewhat, against a spring 73. The lever 65 is pivoted about pins 64 in the member 60, as is an upper lever 76 which has a cam follower 77 at its upper end. This cam is urged against the cam 122 by a garter spring 80. The lever 76 is connected to an upper extension 75 of the lever 65 by a spring 83 which is connected at one end to a screw 84 in the extension 75. The screw 84 is adjusted to vary the tension in the spring 83. Movement of the lever 76 towards the spindle 30 is limited by a headed pin 85 extending from the extension 75 with its head in a recess in the lever 76, but this pin allows a limited amount of movement in the opposite direction against the spring 83. Thus the roller 66 can adjust itself when engaged with the cap C to accommodate, within preset limits, variations in container mouth or neck size. The pilfer-proof band forming mechanism is similar, except that the shaft 98 carrying the roller 96 is vertical. Each spindle carries two each of the rollers 66 and 96. After the cap is formed on the container it is ejected from the head as the piston 20 is raised by a spring loaded stripper 134.